<!DOCTYPE html>
<p style="height: 100px">
Tests paint invalidation of column rules when column changes without changing geometry of the column and the column set.
Passes if no under-invalidation is reported.
</p>
<div id="columns" style="columns: 2; background-color: blue; column-rule: 2px solid green; width: 200px; height: 200px">
  <div id="content1" style="display: inline-block; width: 50px; height: 200px; background-color: yellow"></div><br>
  <div id="content2" style="display: inline-block; width: 50px; height: 100px; background-color: yellow"></div>
</div>
